[Bug target/107916] New: PPC VSX code generation for OpenZFS

[dje at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=107916

            Bug ID: 107916
           Summary: PPC VSX code generation for OpenZFS
           Product: gcc
           Version: unknown
            Status: UNCONFIRMED
          Severity: enhancement
          Priority: P3
         Component: target
          Assignee: unassigned at gcc dot gnu.org
          Reporter: dje at gcc dot gnu.org
                CC: bergner at gcc dot gnu.org, segher at gcc dot gnu.org
  Target Milestone: ---
            Target: powerpc64le-*-linux

https://github.com/openzfs/zfs/pull/14234

GCC codegen https://gcc.godbolt.org/z/bhPo9sWsx

Clang codegen https://gcc.godbolt.org/z/4rTEe3WMG

Clang is relatively compact and efficient
.LBB0_2:                                # =>This Inner Loop Header: Depth=1
        lxvd2x 1, 0, 4
        addi 4, 4, 16
        xxswapd 1, 1
        xxmrghw 40, 0, 1
        xxmrglw 41, 0, 1
        vaddudm 7, 7, 8
        vaddudm 6, 6, 9
        vaddudm 1, 7, 1
        vaddudm 5, 6, 5
        vaddudm 0, 1, 0
        vaddudm 4, 5, 4
        vaddudm 3, 0, 3
        vaddudm 2, 4, 2
        bdnz .LBB0_2

GCC is rather less efficient.